The present invention relates to a connector for a temperature sensing probe of a microwave oven, and more particularly, to a device that connects a temperature sensing probe to the control circuit of the microwave oven, wherein said temperature sensing probe is inserted into the food being cooked rotates together with the turntable of the microwave oven.
A typical microwave oven incorporating heat control means that respond varying temperature and which can be monitored during the food cooking operation is already commercially available. Such a microwave oven is designed so that the temperature can be properly controlled, for example, by inserting a temperature sensing probe containing a thermister incorporated in the tip portion of a metal needle tube into the food in order that temperature data detected by the thermister can be sent to the heat source control circuit such as a magnetron of the microwave oven.
On the other hand, while operating a microwave oven that uses a turntable for rotating the food during the cooking operation and the temperature control means mentioned above, the food being cooked rotates together with the temperature sensing probe. This makes it quite necessary that the temperature sensing probe be properly connected to the microwave oven so that it can freely rotate throughout the cooking operation.
As shown in a sectional view in a conventional connector of FIG. 1 and the plane view thereof in FIG. 2, a typical device connected to a freely rotating temperature sensing probe incorporates a structure comprising bushes 2a and 2b in choke 1 that is secured to the microwave oven unit so that the relay jack 3 is freely rotatably supported by bushes 2a and 2b. A plug connected to one end of the temperature sensing probe is inserted into the relay jack 3 in order that the plug can rotate together with the relay jack, thus causing the contact elements 4a and 4b to be elastically placed into contact with guide plates 41 and 42 that are provided at one end of the relay jack 3, and enabling the temperature data to be record. Details of this mechanism were disclosed by U.S. Pat. No. 4,149,056 "MICROWAVE OVEN WITH FOOD TEMPERATURE-SENSING MEANS" to Kaneshiro et al.
With reference to the mechanism of the conventional connector discussed above, not only the guide plates 41 and 42, but also a variety of parts such as a plug hold spring 33', a jack cylinder 44, and many other elements are required for the relay jack 3. In addition, since the connector has a complex structure, it cannot be easily produced. As a result, the cost still remains very high.
In the light of such disadvantages, the present invention is primarily directed to providing a connector that enables a rotating temperature sensing probe to be effectively connected to the connector while at the same time being composed of a simple structure by minimizing the parts being used.
A preferred embodiment of the present invention provides an improved connector of the temperature sensing probe for connection with the control circuit of a microwave oven to permit the probe to freely rotate together with the turntable when it is inserted into food during the cooking operation. More particularly, an improved connector comprises a freely rotating cylinder made of an insulation material, which is installed in a choke secured to the microwave oven unit. The connector contains first and second springs which are made of a conductive material and secured to the cylinder, one end of which makes up a plane surface along one end of the surface of the cylinder. The other end thereof makes up an elastic part along the inner surface of said cylinder, and the first and second contact elements elastically come into contact with the plane surfaces of the first and second springs. A plug at the tip portion of said probe is supported by the elastic parts of both the first and second springs, and as a result, the plug is supported by said choke in a freely rotating state via said cylinder, thereby eventually allowing said contact elements to send out the temperature data detected by the temperature sensing probe.
Another preferred embodiment of the present invention provides means, in which the choke lid secured to the microwave oven unit is made a throttle plate, whereas a cylinder of a large diameter is projectively installed in the center position of said choke lid via an opening which passes through the plug of the temperature sensing probe to enable the choke lid and choke itself to be coupled together. If necessary, a spacer is provided in the choke opening so that the spacer behaves as a guide to enable the plug of said probe to be inserted into said opening.